The Oat Hill Mine Trail is an 8.3-mile hike that climbs through volcanic rock and chaparral just outside Calistoga, offering real elevation gain and views that expand as you go higher. Your dog can come along on leash, though they’re not allowed off-trail in the adjacent Robert Louis Stevenson State Park, so stick to the main path.

The lower sections give you sweeping views of Napa Valley’s vineyards spreading out below, but the real payoff comes as you climb through the middle and upper segments where volcanic formations create a landscape that feels genuinely wild. You’ll walk through oak and Douglas fir forests, grassy meadows, and if you time it right in spring, fields of wildflowers. The trail itself is rocky in places and genuinely challenging—this isn’t a casual walk, but it’s worth the effort if you and your dog are up for something substantial.

The trail follows the historic route that once connected Calistoga to Pope Valley during the mining era. The old mercury mines to the north aren’t open to visitors, but the landscape tells the story of that industrial past. You get a sense of how remote this area was when those operations were active.

Water is crucial here. Bring enough for both of you since there’s no reliable water source along the trail. The upper section sometimes closes in late summer due to fire danger and during deer hunting season, so check conditions before heading out. If you’re planning to tackle the full 8.3 miles, budget a good chunk of time—it’s not just the distance but the elevation that makes it a full day activity.

Start early if you can. The lower elevations get sun exposure, and your dog will appreciate hitting the shadier forest sections once you’ve warmed up. The parking area at the trailhead fills up on weekends, particularly during the cooler months when the trail is most accessible.